Omeros Corporation Announces FDA Approval of OMIDRIA®
for Use in Pediatric Patients

-- FDA Also Grants Additional Market Exclusivity --

December 12, 2017 07:00 AM Eastern Standard Time

SEATTLE--(BUSINESS WIRE)--Omeros Corporation (Nasdaq: OMER), a commercial-stage biopharmaceutical
company committed to discovering, developing and commercializing
small-molecule and protein therapeutics for large-market as well as
orphan indications targeting inflammation, complement-mediated diseases
and disorders of the central nervous system, today announced that the
U.S. Food and Drug Administration (FDA) approved Omeros’ supplemental
new drug application (sNDA) following review of efficacy and safety data
from a pediatric clinical trial, expanding the indication for OMIDRIA
(phenylephrine and ketorolac intraocular solution) 1% / 0.3% to include
use in pediatric patients (ages birth through 17 years old). OMIDRIA,
used during cataract surgery or intraocular lens (IOL) replacement,
prevents intraoperative miosis (pupil constriction) and reduces
postoperative pain. FDA approved the sNDA for OMIDRIA under priority
review.

The successful clinical trial was conducted in 78 pediatric patients
randomized to either OMIDRIA or phenylephrine administered
intraoperatively. Together with the label expansion now including both
pediatric and adult patients, FDA also granted OMIDRIA an additional six
months of U.S. market exclusivity. Under section 505A of the Federal
Food, Drug, and Cosmetic Act, this six-month extension of market
exclusivity is attached to the term of the drug’s patents listed in
FDA’s Orange Book.

“We are pleased that FDA has approved the use of OMIDRIA in pediatric
patients and granted additional market exclusivity,” said Gregory A.
Demopulos, M.D., chairman and chief executive officer of Omeros. “Now
all patients undergoing cataract or other lens replacement surgery can
receive the benefits of OMIDRIA. These procedures are more complex in
pediatric patients than in adults, and it’s gratifying to know that our
drug will be helping children.”

Omeros previously announced a favorable settlement of its patent
infringement lawsuit against Par Pharmaceutical, Inc. and its subsidiary
Par Sterile Products, LLC (Par) in which Par acknowledged and confirmed
the validity of the Orange Book-listed patents for OMIDRIA. Unless
subsequently authorized pursuant to terms in the settlement agreement,
Par is prohibited from launching a generic version of OMIDRIA until
April 1, 2032. These same patents are similarly being asserted against
Sandoz Inc. and Lupin Ltd. in Hatch-Waxman litigation planned for trial
in mid-2019 in the U.S. District Court for the District of Delaware, the
same court that presided over the Par case. If that court upholds and
finds infringement of any claim in the Orange Book-listed patents for
OMIDRIA that expire in October 2033, Sandoz and Lupin, as a result of
the newly granted market exclusivity, will be precluded from launching a
generic version of OMIDRIA until April 2034.

About OMIDRIA®Omeros’ OMIDRIA®
(phenylephrine and ketorolac intraocular solution) 1% / 0.3% is the only
FDA-approved product for use during cataract surgery or intraocular lens
replacement to maintain pupil size by preventing intraoperative miosis
(pupil constriction) and to reduce postoperative ocular pain. OMIDRIA
also is the only NSAID-containing product FDA-approved for intraocular
use. In post-launch studies across conventional and femtosecond
laser-assisted cataract surgery, OMIDRIA has been shown (1) to be
effective in patients with intraoperative floppy iris syndrome (IFIS),
pseudoexfoliation and other ophthalmic conditions, (2) to significantly
reduce complication rates, use of pupil-expanding devices, and surgical
times, and (3) to significantly improve uncorrected visual acuity on the
first day following cataract surgery. While OMIDRIA is broadly indicated
for use in cataract surgery, the above outcomes are not in its currently
approved labeling. Surgical time was not an endpoint in the OMIDRIA
Phase 3 clinical trials and did not reach statistical significance in
post hoc analysis of the Phase 3 data.

Important Safety Information for OMIDRIA®Systemic
exposure of phenylephrine may cause elevations in blood pressure. In
clinical trials, the most common reported ocular adverse reactions at
two percent or greater are eye irritation, posterior capsule
opacification, increased intraocular pressure, and anterior chamber
inflammation; incidence of adverse events was similar between
placebo-treated and OMIDRIA-treated patients. OMIDRIA must be added to
irrigation solution prior to intraocular use.

About Omeros CorporationIn addition to Omeros’ commercial
drug OMIDRIA, Omeros has multiple Phase 3 and Phase 2 clinical-stage
development programs focused on: complement-associated thrombotic
microangiopathies; complement-mediated glomerulonephropathies;
Huntington’s disease and cognitive impairment; and addictive and
compulsive disorders. In addition, Omeros has a diverse group of
preclinical programs and a proprietary G protein-coupled receptor (GPCR)
platform through which it controls 54 new GPCR drug targets and
corresponding compounds, a number of which are in preclinical
development. The company also exclusively possesses a novel
antibody-generating platform.

Forward-Looking StatementsThis press release contains
forward-looking statements within the meaning of Section 27A of the
Securities Act of 1933 and Section 21E of the Securities Exchange Act of
1934, which are subject to the “safe harbor” created by those sections
for such statements. All statements other than statements of historical
fact are forward-looking statements, which are often indicated by terms
such as “anticipate,” “believe,” “could,” “estimate,” “expect,” “goal,”
“intend,” “likely,” “look forward to,” “may,” “plan,” “potential,”
“predict,” “project,” “should,” “will,” “would” and similar expressions
and variations thereof. Forward-looking statements are based on
management’s beliefs and assumptions and on information available to
management only as of the date of this press release. Omeros’ actual
results could differ materially from those anticipated in these
forward-looking statements for many reasons, including, without
limitation, risks associated with product commercialization and
commercial operations, unproven preclinical and clinical development
activities, regulatory oversight, intellectual property claims,
competitive developments, litigation, and the risks, uncertainties and
other factors described under the heading “Risk Factors” in the
company’s Quarterly Report on Form 10-Q filed with the Securities and
Exchange Commission on November 9, 2017. Given these risks,
uncertainties and other factors, you should not place undue reliance on
these forward-looking statements, and the company assumes no obligation
to update these forward-looking statements, even if new information
becomes available in the future.